Refractive errors occur when the cornea and lens cannot focus light on the retina (light - sensitive layer at the back of the eye)
Glasses or contact lenses restore the clearness of vision
Myopia (nearsighted patients)
Near objects seen clearly
Eye has too much plus power
Eye's focus falls in front of retina
Eye length usually too long
Minus powered lenses required (-)
Hyperopia: farsighted patients
Eye length usually too short
Eye's focus falls in the back of retina
Eye has too little plus power
Plus powered lenses required (+)
Astigmatism:
Eye does not focus evenly
Lenses with cylinder power required
Presbyopia:
Inability of the eyes to do near work
Occurs around 40-44
Additional plus power for near required
Reading glasses, progressives, bifocals
Cataract: A clouding of a lens of your eye
Requires surgery to restore vision